The majority of states have legalized medical marijuana (MM) despite its Federal Schedule 1 designation as an illegal substance. Public schools must comply with Drug Free Workplace laws or risk the loss of federal funding. To address the conflict between state and federal laws regulating MM, the National Association of School Nurses issued a position brief in January 2019. The accompanying article introduces the Cannabis/Marijuana Position Brief and provides guidance for school nurses who encounter a student treated with MM. Topics addressed include background implications of federal marijuana and hemp law, mechanism of action for MM, Epidiolex overview, current research regarding efficacy of MM for common qualifying conditions, and implications for school nursing practice.